package com.three.jvm.test1;

import java.util.HashMap;

/**
 * @author zhouyanxiang
 * @Date 2021-04-2021/4/14-11:15
 */
public class Main {

    public static void main(String[] args) {
        HashMap<Integer, Integer> map = new HashMap<>();
        map.put(1,3);
        Integer integer = map.get(1);
        System.out.println(map.containsKey(2));
    }
    
}
